PHILADELPHIA — Once the clear front-runner to be the Democratic nominee for governor of Pennsylvania, Rep. Allyson Y. Schwartz sounded annoyed as she spoke up during a candidates debate to correct the moderator on a key point — her name.

“Schwartz,” the five-term member of Congress said swiftly, after being called “Ms. Schultz.” Then, as if pleading for affirmation, she added: “You know me.”

The February exchange, prompted by an innocent slip of the tongue, was an early indicator of the frustrations that have engulfed the once-promising candidacy of Schwartz, a fixture in Democratic politics here for two decades who, polls show, is likely to lose in Tuesday’s primary. The new front-runner is Tom Wolf, a wealthy businessman who has spent $10 million of his own money to present himself as a small-town, Jeep-driving outsider.

Schwartz has built her campaign on her experience as a legislator, and she expected that her résumé would help carry her to the Democratic nomination and give her a shot at becoming the first female governor of the nation’s sixth-most-populous state.

Yet Schwartz has not been able to translate her regional name recognition into a persona with appeal across a demographically diverse state.

Many voters consider her experience in dysfunctional Washington to be a potential flaw rather than a plus. And the state Democratic establishment, eager for a candidate perceived as a stronger challenger to Gov. Tom Corbett (R) in November, has all but cast Schwartz aside, with influential figures such as former governor Edward G. Rendell and Philadelphia Mayor Michael Nutter staying on the sidelines — seen by some as tacit endorsements of Wolf.

Schwartz “ran a bad campaign,” said Rendell, a former mayor of Philadelphia. “Schwartz was a little better known [than Wolf], but a congressman is not a mayor. I think she thought she had the same hometown appeal as I did.”

Trailing Wolf by 20 or more points in recent polls, Schwartz has spent the final days of the primary campaign trying to connect with the voters who should feel the most comfortable with her: Democrats in and near her suburban Philadelphia district. On a swing late last week, as she had done with the debate moderator, Schwartz repeatedly told voters that, indeed, they do (or should) know her. But it sounded like she was also reaffirming that to herself.

“I know how to get things done, but you know me,” she told a man sitting at a table, as he sucked the bone of a baby-back rib.

To a man on a street corner, she said: “I’ve been around awhile, you’re right to know me.”

“They all feel like they know me,” she told a campaign aide.

When a produce cashier in the Reading Terminal Market smiled and waved, she told a reporter, “See, they recognize me.”

Meanwhile, about a 30-minute drive from Schwartz’s home, at an outdoor farmers market deep in her district, her constituents swarmed Wolf, a balding, middle-aged man with a white-and-gray-specked beard.

Montgomery County Commissioner Josh Shapiro, considered a rising star in the state Democratic Party, played host to Wolf in Schwartz’s district. He publicly got behind Wolf’s candidacy a few weeks ago. “People are yearning for a transformational governor,” he said.

Wolf, a former Peace Corps volunteer from central Pennsylvania, has offered a personal story that seems tailor-made for an anti-politician era. Ads he began airing at the beginning of the year, produced by veteran Democratic consultant Saul Shorr, featured Wolf’s two daughters, his wife and his mother talking about his résumé. The spots have featured Wolf driving his beat-up 2006 Jeep Wrangler down a neighborhood road as he honks and waves.

Wolf became a millionaire when he sold his family cabinetry business. He worked as the state’s revenue secretary under Rendell in 2007 and 2008, and considered running for governor in 2010. But his old business was floundering under the weight of the recession, so he bought it back and worked to save the company.

With the flurry of ads, Wolf was the first to introduce himself to voters, while Schwartz and two other candidates, state Treasurer Rob McCord and former state environmental secretary Katie McGinty, focused on fundraising. By the time the other candidates began airing ads two months later, Wolf was well-known, as were his family and his Jeep.

Last-ditch efforts by Wolf’s rivals to attack him — in one case an implication of racism, a charge he vehemently denied — do not appear to have dented his standing in the polls.

Wolf’s sudden rise has surprised many Pennsylvania political experts, who say they have never seen a political newcomer shoot so quickly to the top.

“This was a virtual unknown who within three weeks has lurched into a lead that has essentially not dissipated,” said Terry Madonna, a veteran pollster at Franklin & Marshall College.

As Wolf has captured the spirit of a disgruntled electorate, Schwartz has run as the candidate with experience in state and national legislating.

She has highlighted her years in Washington, where she has built a deep national Rolodex from her time as chief fundraiser for the congressional Democrats’ campaign arm and where she holds a seat on the House Ways and Means Committee.

She has also embraced her relationship with President Obama. One ad boasted of her work supporting the Affordable Care Act. Large 8-by-10-inch mailers show her smiling with the president.

But some Democratic leaders have quietly groused that Schwartz is giving up her congressional seniority, valuable for Pennsylvania, to make a potentially ill-fated bid for governor. And she has struggled to find her niche politically.

“Her blessing and her curse was that she had a base of people that supported her from one election to the other, but she was never able to expand beyond the supporters she had,” said Alan Kessler, a longtime Pennsylvania fundraiser.

Schwartz has tried to keep things positive on the campaign trail.

When a voter recently asked about her standing in the polls, she laughed nervously and described herself as “within range.”

In an interview, she acknowledged that she doesn’t have the party’s institutional support, but she described the dynamics as her vs. the old boys club in Harrisburg.

She dismissed Wolf as a candidate with “lovely ads” but said voters will realize that they do not know him — unlike her.